1. Field of the Invention
The present invention relates to a cassette tray and a carrier module, and in particular relates to a cassette tray and a carrier module which are used to receive a circuit board.
2. Description of the Related Art
Currently, various carrier modules which are used to facilitate the transportation of circuit boards have been developed. Prior to the transportation of the circuit boards, the circuit boards are automatically or manually placed on a cassette tray of the carrier module. Next, the cassette tray and the circuit boards are moved to a transporting tray which is disposed on a moving mechanism (e.g. a trail) and moved by the moving mechanism.
The circuit board with more than one memory unit is commonly referred to as a DIMM (dual in-line memory module), and two types of circuit boards, a long DIMM and short DIMM, can be further defined according to the dimensions of the circuit boards. To transport these two types of circuit boards, at least two different cassette trays with two specifications should be provided. However, in order to simultaneously receive long DIMMs and short DIMMs when manufacturing a large number of circuit boards, a corresponding number of the two different cassette trays should be provided. This leads to a large amount of excess inventory and causes increased manufacturing cost.
Meanwhile, because a conventional robot cannot operate with high accuracy, a plurality of compartments is formed between each of two passages to ensure that the circuit boards are placed on the cassette tray correctly. Meanwhile, when the circuit boards are placed on the cassette tray manually, the circuit boards may be hit by the compartments easily. Moreover, the width of the passages for receiving the circuit boards is too large to keep the circuit board straight. Thus, an abnormal tilted angle of the circuit board may occur, which may affect the accuracy of the robot and cause the circuit boards to not be able to be held properly. Therefore, these issues should be resolved by developing a better cassette tray and carrier module.